Well, the thing about armors are that they take up an item from the item list. Unfortunately, items are severely limited because we can't create and register news ones, or at least we haven't figured out how to do it yet. This means that in order to have even 1 new armor set would mean removing an existing item from the game. You can see where this would quickly become a problem for 7 clans and 2 genders.

There is a bug in the core game: if you're wearing e.g. light leather and you sell it, you keep the armor rating but switch back to the light clothes model. Then if you later buy a new set of light leather, the armor rating is added. For this reason the patch and subsequently all the mods made armor unsellable.